As a conventional system for detecting an object around a vehicle with sensors fixed to the door mirrors, a monitoring system for a vehicle disclosed in Patent Document 1 is known, for example. The system operates as a vehicle monitoring system by detecting the following vehicle and the like in a blind spot of the door mirrors during traveling, or by monitoring an object at rear lateral sides of the vehicle during parking with ultrasonic sensors fixed to the door mirrors.
Patent Document 1: Japanese Patent Laid-Open No. 10-100795/1998.
The conventional system always sets the detection areas of the ultrasonic sensors fixed to the door mirrors diagonally behind the vehicle. For this reason, although it can detect the following vehicle in the blind spot of the door mirrors while the vehicle is traveling, it cannot search for a parking space where the vehicle is to be parked.
In addition, the conventional system forms the detection areas of the ultrasonic sensors at rear lateral sides of the vehicle by folding and retracting the door mirrors when the vehicle is stopped. This enables the same ultrasonic sensors fixed to the door mirrors to detect an object at the rear lateral sides of the vehicle. The conventional system, however, cannot alter the search frequency or search range of the ultrasonic sensors in accordance with the difference in the operation mode when the vehicle is running or stopped or in accordance with the result of the vehicle monitoring, thereby being unable to operate the sensors efficiently.
For example, at parallel parking, it is not necessary to continuously drive the sensors throughout traveling, but to operate the sensors when the vehicle reduces its speed for searching for a parking space. In addition, it is necessary to detect the parking space accurately by increasing the detection range and broadening the directivity angle of the sensors and by increasing the search frequency. On the other hand, in the case of using as the vehicle monitoring system while the vehicle is stopped, unlike the case of searching for the parking space, it is not necessary to drive the sensors frequently, but is enough that the surroundings of the vehicle are within the search range so that a remote unnecessary obstacle is not detected.
The present invention is implemented to solve the foregoing problems. Therefore it is an object of the present invention to provide a sensor system for a vehicle capable of searching for a parking space during running and capable of vehicle monitoring while the vehicle is stopped by using the sensors fixed to the door mirrors, and capable of operating the sensors efficiently in accordance with the difference in the operation mode when the vehicle is running or stopped, or in accordance with the result of the vehicle monitoring.